[sokoloff]

All true (except multiply all those dollar figures by a factor of 4).

The problem is that I'd be taking on a new 30-year mortgage while being about 10 years away from retirement rather than ~26 years away from retirement, which has certain implications on my ability to afford that mortgage over its full term.

[woobar]

When you are retired you don't need to live at the same place. World is your oyster. The capital gains from your house ($1.2M already, more in 10 years) will allow you to pick new house almost anywhere without worrying about mortgagees. You won't care about schools or extra bedrooms for kids, for instance.

Statistically very few people stay at the same house for 30+ years, most move within eight.